.\" Copyright (C), 1995, Graeme W. Wilford. (Wilf.)
.\"
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.\" Wed Jun 14 16:10:28 BST 1995 Wilf. (G.Wilford@@ee.surrey.ac.uk)
.\"
.TH RE_COMP 3 2021-03-22 "GNU" "Linux Programmer's Manual"
.SH NAME
re_comp, re_exec \- BSD regex functions
.SH SYNOPSIS
.nf
.B #define _REGEX_RE_COMP
.B #include <sys/types.h>
.B #include <regex.h>
.PP
.BI "char *re_comp(const char *" regex );
.BI "int re_exec(const char *" string );
.fi
.SH DESCRIPTION
.BR re_comp ()
is used to compile the null-terminated regular expression pointed to by
.IR regex .
The compiled pattern occupies a static area, the pattern buffer,
which is overwritten by subsequent use of
.BR re_comp ().
If
.I regex
is NULL,
no operation is performed and the pattern buffer's contents are not
altered.
.PP
.BR re_exec ()
is used to assess whether the null-terminated string pointed to by
.I string
matches the previously compiled
.IR regex .
.SH RETURN VALUE
.BR re_comp ()
returns NULL on successful compilation of
.I regex
otherwise it returns a pointer to an appropriate error message.
.PP
.BR re_exec ()
returns 1 for a successful match, zero for failure.
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.ad l
.nh
.TS
allbox;
lbx lb lb
l l l.
Interface	Attribute	Value
T{
.BR re_comp (),
.BR re_exec ()
T}	Thread safety	MT-Unsafe
.TE
.hy
.ad
.sp 1
.SH CONFORMING TO
4.3BSD.
.SH NOTES
These functions are obsolete; the functions documented in
.BR regcomp (3)
should be used instead.
.SH SEE ALSO
.BR regcomp (3),
.BR regex (7),
GNU regex manual
.SH COLOPHON
This page is part of release 5.13 of the Linux
.I man-pages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
\%https://www.kernel.org/doc/man\-pages/.
